How do I set the latency compensation in Logic Pro for re-amping to QC

I am using the QC as my audio interface

If I have the DI signal recorded into Logic Pro and want to re-amp it to the QC, I know I can add the I/O plugin on the track in Logic but, what would the inputs/outputs be so that I can “Ping” to determine the latency compensation?

Thank you

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The outputs should be the inputs on the QC:

  • output on logic IO to USB 5, input on the QC on a “clean” row on USB 5.
  • input on the logic IO to USB 7, output on the QC on the same “clean” row on USB 7.

Do the ping and check the samples. Correct the recording delay on the logic audio config accordingly.

Example:


and

Hope this helped.

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Thank you — But, how does a clean/empty signal chain relate to the sample delay when you are actually using blocks in the QC? or, does that not matter at all and it will be the same regardless of how many amps, FX, and cabs used in the QC when re-amping?

If you change the blocks used, the latency will change. In my example I have on rows 1-2 all the blocks I’ll be using to reamp (it’s not relevant if they’re on or off), so I’m measuring the latency I need to compensate for that specific signal flow.
If you change the blocks (replace, remove or add), you’ll need to measure again.

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But the lane you have USB 7 / 8----------------------------USB 5 / 6 is completely empty so, is the ping merely measuring an empty lane?

What am I missing? (not being obtuse)

My understanding (with help from @VanDaven video - https://www.youtube.com/watch?v=_i7bLnbmRE8 ) is that due to QCs latency compensation the inputs and outputs on different rows will have the same latency (to avoid phasing issues between the rows).

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So, to compensate for the delay, I would have both the I/O plugin on the track in Logic and also set the Recording delay in the Logic Settings to the same number of samples listed in the I/O plugin?

I watched @vandaven video you linked but, I did not comprehend any of the routing going on therein so I will take your word for it that the latency is exactly the same whether you have no blocks in a lane or the lane is replete with blocks

That being said, what if one of the blocks has guitar pedals in the FX loop? Would that not increase latency or is it the same based upon @VanDaven video?

Also, say, for example, a factory preset like 29C Hysteria – that uses all 4 lanes - how would you Ping that, considering there is nowhere to add a clean/empty lane?

I swear I am on the verge of just going back to playing acoustic guitar and forgetting trying to figure all this out - I do appreciate your time and effort in trying to assist me

If all the rows are used, I have no idea how to measure this :slight_smile:

I’d say that at the end of the day, it really depends on how accurate you want the recording to be. Depending on the latency it may not be worth going through all the trouble… YMMV

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The delay calculated by the I/O Utility plugin (after pinging) is automatically compensated by Logic. There is no need to go into “Recording Delay” and adjust the samplers.

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OK thank you - hopefully someone who knows the answer can chime in

Ahhh ok, thank you

Good to know. It makes sense if you leave the I/O plugin on :slight_smile: I was not…

tks!

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I am emailing NDSP support and will report back any information

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